There is no protection measure generally for a coil of an existing alternating current contactor under normal circumstances. But under special environments, the coil can be protected with the assistance of a surge suppressor. However, the surge suppressor needs to be connected with the coil, and in order to approach to the coil, it is necessary to provide a mounting groove or a concave hole near the coil to place the surge suppressor. The surge suppressor is mounted inside a product and occupies a large area, which makes the design of a base more complicated, and increases the design difficulty and the machining difficulty of a mold and results in low production efficiency. In addition, it is necessary to mount the surge suppressor inside the product during assembling, so the process is more complicated and not inconvenient for assembly.
Moreover, with respect to the existing contactor, it is often to cause the failure of integral assembly of the product due to machining errors, this is mainly because of the lack of an adjusting structure for adjusting a total stroke of the product, thereby bringing great convenience for production. For example, contact surfaces of a coil frame of the existing contactor close to the base are all planes, so as to avoid interference with the base structure, and the mold manufacturing process is relatively simple and convenient for measurement. However, the amount of compression of supports is limited by the entire planes, so it is not possible to adjust the total stroke of the product through the dimension of the coil frame. Moreover, the supports are adopted to fix a magnetic yoke in the existing contactor to play a certain buffering role. Each support generally uses a symmetric non-eccentric structure. Although the mold manufacturing process is simple, it is not possible to adjust parameters by forward or inverse assembly if the parameters, such as the total stroke of the contactor are not consistent, so the flexibility is poor. Plastic parts, owing to changes in material, process, deformation, etc., easily lead to non-compliance of dimensions, resulting in changes in the dimension of the total stroke, which will cause the total stroke to be too large or too small, thus affecting the overtravel of the product and affecting the reliability of the product.